MKT-00759 Rev A

© Synaptive Medical Inc. 2020. Prepared in Canada. All rights reserved. Errors and omissions excepted. SYNAPTIVE, the Synaptive logo, and Modus V are trademarks of Synaptive Medical Inc., or its subsidiaries. Other trademarks are the property of their respective owners. Patents Pending. Permission has been obtained to use all anonymized images in this case study for publication purposes. Please contact Synaptive for information on the regulatory clearance status in your jurisdiction.

C7-T1 Anterior Cervical Discectomy and Fusion

Douglas Blaty, DO, Inland Northwest Spine and Neurosurgery

Clinical Presentation The patient is a 45-year-old male with a 1-year history of worsening mechanical neck pain and bilateral pain and numbness in a C8 distribution. Arm pain and numbness is worse with neck extension, and better with flexion. The patient’s neck pain is at the cervico-thoracic junction and spreads to the periscapular region, and is worse with neck motion. He has a history of a C4-6 Anterior Cervical Discectomy and Fusion (ACDF) six years prior, with stable pseudarthrosis at both levels. Recent C7-T1 Epidural Steroid Injection gave near complete relief of neck and arm pain for 1 week.

The patient presented with a barrel-chest shape. No signs of motor deficits in bilateral upper extremities, and sensation is intact to light touch from C4-T1 bilaterally, with subjective paresthesias in a bilateral C8 distribution. No upper motor neuron signs.

Figure 1: Pre-operative imaging: Cervical x-ray and CT scan show a C7-T1 5mm spondylolisthesis with vacuum disc phenomenon. Old C4-5 and C5-6 ACDF has a stable pseudoarthrosis, with auto-fusion at C6-7.

Figure 2: Pre-operative imaging: Cervical MRI shows C7-T1 spondylolisthesis with moderate central canal stenosis, and severe bilateral foraminal stenosis (arrows).

Figure 3: Pre-operative imaging: Swimmer’s view x-ray to show cerivothoracic junction.

Swimmer’s view lateral x-ray shows that the approach to C7-T1 is not only very steep, but due to the patient’s anatomy and barrel-chest, the clavicle and manubrium are in close proximity to where the approach to the anterior cervical spine would need to be located.

Surgical Management Modus V™ was placed at an estimated 50-60º angle from vertical, even with the patient in a slight Trendelenburg position, to optimize the view.

Due to C7-T1 spondylolisthesis and barrel-chest of the patient, this procedure would have been extremely difficult to perform even with loupes, and extremely uncomfortable and poorly ergonomic with a traditional microscope.

MKT-00759 Rev A

© Synaptive Medical Inc. 2020. Prepared in Canada. All rights reserved. Errors and omissions excepted. SYNAPTIVE, the Synaptive logo, and Modus V are trademarks of Synaptive Medical Inc., or its subsidiaries. Other trademarks are the property of their respective owners. Patents Pending. Permission has been obtained to use all anonymized images in this case study for publication purposes. Please contact Synaptive for information on the regulatory clearance status in your jurisdiction.

With Modus V holding the difficult position, the case was like any other ACDF as the surgical team was standing in an upright and normal position.

Figure 4: Intra-operative room setup with Modus V highlighting the extreme lateral positioning of the optics to provide the required view of the C7-T1 surgical site without compromising the surgeon’s ergonomics.

Figure 5: Example ACDF surgical image from Modus V highlighting the delineation between the dura and the Posterior Longitudinal Ligament (arrow), often not visible with loupes or a microscope.

Figure 5: Intra-operative view of ACDF set-up with Synaptive, highlighting the ample working room and the OR team collaboration while working off the same surgical monitors.

Conclusion Post-operative x-rays show C7-T1 ACDF with titanium interbody device and anterior plate and screws, below previous C4-6 ACDF construct. The patient had almost full reduction of C7-T1 spondylolisthesis, with good height restoration.

Figure 7. Post-operative imaging showing C7-T1 ACDF below previous C4-6 ACDF construct.

The patient had immediate resolution of bilateral arm pain and numbness, and near complete resolution of pain at the base of the neck.

Highlights • Modus V enabled what would have been an extremely difficult procedure by providing the

surgical visualization required, while allowing the surgical team to stand in an upright, ergonomically neutral position.

• The patient had immediate resolution of arm pain and numbness, and near complete resolution of neck pain.